The human eye, in simple terms, functions to provide vision by refracting light passing through a clear outer portion called the cornea and focusing the light by way of the lens onto the retina at the back of the eye. The quality of the visual image created by the focused light depends on many factors including the size, shape, and length of the eye, and the shape and transparency of the cornea and lens.
When trauma, age, or disease causes the lens to become less transparent, vision deteriorates because of a reduction in light transmitted to the retina. This deficiency in the eye's lens is medically known as a cataract. The treatment for this condition is often surgical removal of the natural lens and implantation of an artificial lens, typically termed an Intra-ocular Lens (IOL).
Insertion of an IOL is typically performed using an IOL insertion tool. A conventional IOL insertion tool includes an IOL insertion cartridge that may fold and insert the IOL through a relatively small incision into the eye. For example, the IOL cartridge may include a folding chamber that has walls shaped to cause the IOL to fold as desired as the IOL is moved through the chamber. Then, the folded IOL may be deployed into the patient's eye through the small incision. Typically, the operator of the IOL insertion tool manually pushes a fold-plunger that advances the IOL through the folding chamber. The operator also manually pushes the plunger to advance the IOL out of the distal end of the IOL insertion tool and into the patient's eye. However, since the manual force applied to the plunger may vary by use and by operator, the appropriate folding forces may not be achieved in some instances. This can lead to undesirable folding results. Furthermore, the manual force applied to advance the IOL into the patient's eye may vary by use and by operator, leading to inconsistent surgical outcomes. It is desirable to find methods and systems for providing improved and consistent advancement of the IOL through the folding chamber and deployment of the IOL into the patient's eye.